title: Silver Doped 0.9PMN-PT-0.1PZT Composite Films for very High Frequency Ultrasonic Transducer Applications.
abstract: A series of silver doping concentration into the 0.9PMN-PT-0.1PZT (PMN-PT-PZT) films via the composite sol-gel technique were prepared. The crystallographic properties and microstructures of PMN-PT-PZT films with the silver dopant were investigated. Additionally, the effect of silver doping on dielectric and ferroelectric properties was examined. The results show that in general, the dielectric permittivity and remnant polarization increase as the silver doping concentration is increased. The PMN-PT-PZT+ 2.5 mol% Ag film exhibits a dielectric constant of 3,610 at 1 kHz and a remnant polarization of 57.6 µC/cm2at room temperature. From this silver doped film, very high frequency ultrasonic needle transducers were fabricated and evaluated. The representative transducer had the center frequency of 225 MHz with a -6 dB bandwidth of 29% (65 MHz) and 62 dB insertion loss. The performance of this transducer is comparable to other composite sol-gel films transducer. The results suggest that this silver-doped PMN-PT-PZT film is a promising candidate as an alternative piezoelectric film for very high frequency transducer applications.
authors.affiliation: Department of Biomedical Engineering and NIH Transducer Resource Center, University of Southern California, Los Angeles, California 90089 ; Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089.
authors.forename: Hsiu-Sheng
authors.initials: HS
authors.lastname: Hsu
authors.forename: Vatcharee
authors.initials: V
authors.lastname: Benjauthrit
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wei
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Huang
authors.forename: Qifa
authors.initials: Q
authors.lastname: Zhou
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung